Taking human anatomy into account, the toilet facilities on space station have an architecture that expertly aligns the purpose to the environment (such trifles as a toilet seat are not needed when you are weightless). The Soyuz spacecraft is a different matter. The toilet on Soyuz is simple, and will get the job done with minimum mess. But relaxing it is not. In the cramped quarters your crewmates politely keep their backs turned, with plugged noses. Fortunately, we only live in the Soyuz for two days before we rendezvous and dock with the space station. After that we can live, and relieve ourselves, in semi-private style.
The Olympian measure of endurance for a Soyuz crewmember is to hold your bowel for the two-day passage. This is a competition with no place for silver or bronze. Shortly after the hatch opening and the first handshake/hug with our friends already on the station, the newly arriving crew makes a hasty retreat to the toilet. Exercising proper space etiquette, it is best not to give the newly arrived too strong a hug.
To help ease our difficulty, we are offered a pre-launch enema. Administered by our flight surgeons, this allows us to launch with a clear mind and a clean colon.